Art of finishing the edges of flexible material



July 9,1935. M. w. TETLOW 2,007,262

ART OF FINISHING THE EDGES OF FLEXIBLE MATERIAL Filed Aug. 14, 1955 A VE/V TU/f,

. Patented July 9, 1935 a UL.

j io smsmm m EnGEs F .,p,,, LE I ef- E & L v

r 'MBJX'W; Tetlo'w, Boston, Mass.,' assignor to United Shoe MachineryCorporation,.'Paterson,N. J., e "a corporation' efNeivJersey Ai plication August14;;1933; Serial No. 684,956 uscla mssiiol.124146) V This inven'tionrelates to fameth'od or finishing the edge of a pieceof leather or other, flexible sheet material, more particularly to'the" finishing, of the edge of a, pieceof sheet material which is:

-. to'beused as part of the upper of a boot, or shoe; andto 'the article which results frdmthe prac} tics of themethod. r a An edge of apiece of upper-material for use in boots and shoes is commonlyfinished byattache; A ing to the "display side of. said material along saidf edge'onc edge of; a fabric binding strip and ther' afterlfolding the freejpor'tion of the strip about the edge of the sheet material a'ndfoverjupdn the other side of "samjsheet material, cement having r previouslybeen applied to the striportoth mar gin of the sheetmaterial or' to bothfso thatthej binding strip will adhere to'the sheet material. As a result of this procedure, the edge of the sheet materialis covered by a part of the binding strip and'presents a pleasing finished appearance 1 Two procedures for carrying out 'this'general 7 method are inl'common use; Accordin'gjto'one' procedure, thebindingstrip is first sewed t'othe piece of sheet material, a coat of cement isappli'ed to'the'binding stripand to the margin ofjthesheet' material, and then the binding strip is folded over and pressed'into place while the cement is's'till sticky According to the other'procedure; the binding strip is coated with a'thermoplastic' ce ment before being sewed to the sheet material, and

this coating of cement isjsoftened' by heat prior to the foldingoperation.

However, a binding strip coated alljthejivay across its width'with thermoplasticgcein'ent has been found somewhat difiicult to stitch properly 'to the sheet materialbecause then'eedleof the 1 se ing machine is j liable to become g urnrned.

Consequently, when the procedure employing thermoplastic cement is used, the binding strip is commonly. coated with a narrow band of cement along the margin thereofileaving the opposite margin uncoated, and hence in conditionjto be stitched more readily'to the sheet material. The first-named procedure, which makes use of what is called wet cement; which is cdrnmonly Smut-ion? u b i naphtha, s the'dr'awback that because such a cement must stand for a considerable interval before it becomes properly sticky, the pieces of work which have been coated with cement must be handled very carefully until after they have been folded, since otherwise they are liable to stick to and thereby soil one another..

The second procedure (the one employingthermoplastic cement) is not open to this objection because the coating of cement on the strip is in I work after the its normalfhard, non-sticky condition until the piece'ofwork' is to be folded, whereupon thepiece is fcommonlyf passed through a suitable machine which progressively heats the cement and folds the binding strip. This second procedure, how- 5,

ever, has the drawback that in the finished work i the binding', stri'p frequently not attached throughout its whole width to the sheet material but only throughout thettportion of its width which was initially coated with'the cement. In 10 whole or in part of threads .or fibers capableoi being gelatinized by treatment with a solvent for said fibers is attached to the piece of leather or other flexible sheet material and is treated with a solvent prior tothe completion of the folding operation torender it sticky so that it will adhere firmlyft'o'thesheet material. In practicing this methodjthedisadvantages mentioned above in connection with the two commonly practiced procedures are'obviated. Thereis no danger of soil ing'lthe work jlthefbinding strip may be stitched tothe piece or sheet material without difficulty, and in the finished iolded work the binding strip isattached throughout its width to the piece.

7, "Referringjtothe accompanying drawing,

" Fig.1 isv a perspective of a portion'of the upper of aishoe, such as a leather'parato which hasflbeenhstitched a fabricbinding strip consisting in whole or in part of threads or fibers whichihay be gelatinized by treatment with a solvent, v j r I Fig; 2'is a perspectivepf the samezpiece of work showing the application of coating consistingi of or containing solvent to the margin of the piece of leather after the binding strip has been pulled outso as to lie in a plane which'is 40 parallel to that of the leather piece, and

I Fig;"3 a'perspective of the same piece of folding operation has been co np1'et d I practicing the method, the'binding strip at lflllis firstlsewedto the leather piece 200 by arowfof, stitches 300 which are parallel to alined edges'ofthe strip and the piece. This binding strip may conveniently be made of a material known as Celanese which is a fabric made of threads or fibers of cellulose acetate, a substance which may readily be gelatinized by treatment with a solvent such as acetone or various other well-known solvents, or mixtures of solvents, the term solvent being used in a general sense as embracing swelling or dispersing agents for colloids. The binding strip need not be made entirely of soluble threads or fibers provided that it contains enough of such threads or fibers so that the surface of the binding strip, or a. sufficient extent of the surface, becomes properly gelatinized upon treatment with the solvent to cause the strip to adhere to the piece of, sheet material after the strip has been folded about the edge of the sheet material and pressed against a the conditions under whichthe folding operation is carried out, and the sort of leather or upper material the edge of which is to be finished; and the solvent may be applied either to the binding strip or to the margin of the sheet material or to bothQPreferably, the solvent will contain in solution or dispersion sumcient cellulosic or other cementitious substance to render it viscous and will be applied along the margin of the sheet material as illustrated at 400 in Fig. 2. The use of a solvent made properly viscous has two advantages. First, it lessens the tendency which a thin liquid would have to strike through the sheet material and thereby to stain or otherwise injure the display side of said material. For example, if the sheet material is pat- 1 ent leather, any solvent which strikes through 40' will injure the patent leather finish. Second, it permits the production of a firm'bond between the binding strip and the sheet materialwith less gelatinizing of the cellulose acetate or other soluble fibers than would otherwise be the case, since it is not necessary to gelatinize the cellulose acetate sufiicientlyand in suificient quantity so that the gelatinizedsubstance may be forced into the pores or interstices, of the sheet ;material when it is pressed into place as would be the case if a pure solventwere'used. f

Although the method, as specifically described, includes the rendering of the attaching surface of the binding strip. sticky through practically, its whole width, it should be understood thatfthe invention is not limited in its broader aspects to such a procedure.

Having described myin've'ntion, what I claim as new and desire to secure by Letters Patent of the United States is:

1, The method of finishing the'edge of a piece of flexible sheet material which comprises attaching to the display side of the sheet along an edge thereof an edge of a'fabric binding strip consisting in whole or in part of fibers capable of being gelatinized by treatment withasolventg'folding the free portion of the binding strip about. the edge of the sheet and over upon the otherside of the sheet and, prior to the completion of the folding operation, subjecting the soluble fibers to the action of a solvent.

2. The method of finishing the edge of a piece of flexible sheet material which comprises attaching to the display side of the sheet along an edge thereof an edge of a fabric binding strip consisting in whole or in part of fibers of a cellulosic compound capable of being gelatinized by treatment with a solvent, folding the free portion of the binding strip about the edge of the sheet and over upon the other side of the sheet and, prior to the completion of the folding operation, subjecting the soluble fibers to the action of a solvent.

-3. The method of finishing the edge of a piece of flexible sheet material which comprises attaching to the display side of the sheet along an edge thereof an edge of a fabric binding strip consisting in whole or in part of fibers of cellulose acetate capable of being gelatinized by treatment with a solvent, folding the free portion of the binding strip about the edge of the sheet and over upon the other side of the sheet and, prior to the completion of the folding operation, subjecting thesoluble fibers to the action of a' solvent.

4. The method of finishing the edge of a piece of fiexible sheet material which comprises attaching to the display side of the sheet along an edge thereof an edge of a fabric binding strip consisting in whole or in part of fibers capable of being gelatinized by treatment with a solvent, coating the margin of the sheet material with a solvent rendered viscous by the presence in it of a cementitious compound, and folding the free portion of the binding strip about the edge of the sheet material.

5. The method of finishing the edge of a piece ofv flexible sheet material which comprises at-' taching to the display side of the sheet along an edge thereof an edge of a fabric binding strip consisting in whole or in part of fibers capable of being gelatinized by treatment with a solvent, applying to the work a coating of a solvent rendered viscous by the presence in it of a cementitious compound, and folding the free portion of the binding strip about the edge of the sheet material.

' 6. As an article of manufacture a part of the upper of a shoe having stitched to and folded about the edge thereof a binding strip adhesively united to the shoe part by deformed threads which have been gelatinized.

7. The method of finishing the edge of a piece of flexible sheet material which comprises stitchingto the display side of the sheet along an edge thereof an edge of a fabric binding strip consisting in whole or in part of fibers capable of being gelatinized by treatment with a solvent, folding the free portion of the binding strip about the edge of 'the sheet and pressing it upon the other side of the sheet and, prior to the pressing operation, subjecting the soluble fibers .to the action of a solvent.

' 7 MAX W. TE'I'LOW. 

